The death of Muhammad at Medina is followed by the election of the first caliph, Abu Bakr, a father-in-law of the prophet

Omar, another father-in-law of Muhammad, is elected as the second Muslim caliph (the word means 'sucessor to the Messenger of God')

After the assassination of Omar, Othman is elected as the third Muslim caliph

Under the caliph Othman, the revelations made to Muhammad are collected in their definitive form as the Qur'an

Othman is assassinated, and Ali wins power as the fourth Muslim caliph - defeating Muhammad's widow Aisha at the 'battle of the camel' near Basra

Ali is assassinated and Mu'awiya becomes the fifth Muslim caliph, establishing the Umayyad dynasty

With the entire middle east under their control, the Arabs make Damascus the capital of the Umayyad caliphate

The Abbasids massacre the Umayyads in Damascus and establish a new caliphate

The Abbasid caliphs create Baghdad as a new capital city on the Tigris

The luxury of Baghdad, under the caliph Harun al-Rashid, is evident in the Thousand and One Nights

The caliphs in Baghdad begin to employ Turkish slaves, or Mamelukes, in their armies

Togrul Beg enters Baghdad and is granted by the caliph the title of sultan, which becomes hereditary in his Seljuk dynasty

Saladin deposes the Fatimid caliph and brings Egypt back to orthodoxy, acknowledging the rule of the Sunni caliph in Baghdad

When Hulagu and his Mongol army reach Baghdad, in 1258, it is said that 800,000 of the inhabitants are killed - and the caliph is kicked to death

The last Abbasid caliph, captured by the Ottoman Turks, is taken as a prisoner to Istanbul - ending the authentic line of 'successors' to Muhammad

From Bosnia to Egypt and Arabia, the Ottoman Turks now rule the largest Muslim empire since the early caliphate - and will frequently use the title of caliph to assert their authority within Sunni Islam